Polyester verses polyurethane resin

[Tephy]

thought this would be interesting for those wondering what resin to use

https://www.youtube.com/watch?v=DvQNK2RXd3A&feature=youtu.be

 

[Bigblackdog]

what are the standard "acrylic" blanks typically made of? the ones that I have are from timberbits, which work out at about £1.20 each.

The PU certainly seems to have some advantages on this video.

 

[rayf6604]

I think all the blanks I've bought that were polyester said they were in the description. Anything else is possibly not but I'm no expert. However, as I found out recently, using a good tool on polyester and being careful it can be turned without any chip out. He was very rough in the way he attacked those blanks, but the PU stood up to it far better, that's for sure. As for drop test, I've never done it with a made up pen with a polyester blank and I do try to avoid polyester blanks. I've wasted quite a few polyester blanks that have blown out on me.:nonono:

 

[Buckeye]

Turning both types of resin the same way will always show PR in a negative light, you wouldn't turn all woods the same way, especially if heavily spalted. Turn PR the way it should be turned and you will get ribbons flying off as well. PU definitely turns easier there is no debate about that and I have dropped a PR blank on concrete and it broke, I have also dropped a pen with PR and it didn't break or chip, but it did ding the bottom finial.

Peter

 

[Tephy]

I use polyurethane, Timberbits use Acetate ( another form of plastic ) as far as I am aware

 

[Bigblackdog]

I think that the PU resin is much more expensive, so the very cheap blanks are more likely to be PE.

I might give an acrylic a spin the next time I have a chance to get into the workshop. try for myself.

 

[Penpal]

Interesting video.Thanks.
Peter.

 

[Moondoggy]

I bought some off fleabay. They seem to be softer than all of the other, shop bought blanks.
The most noticeable difference is the smell, it almost knocks you out.
I'd be interested to know what the material is.

 

[AndyC65]

I bought some off fleabay. They seem to be softer than all of the other, shop bought blanks.
The most noticeable difference is the smell, it almost knocks you out.
I'd be interested to know what the material is.

That smell is Styrene, I wouldn't advise smelling it. seriously.

Styrene - Wikipedia, the free encyclopedia

Andy C

 

[Moondoggy]

That smell is Styrene, I wouldn't advise smelling it. seriously.

Styrene - Wikipedia, the free encyclopedia

Andy C

I've been using it to freshen my knicker and sock draw, it that wrong?

 

[wm460]

I've been using it to freshen my knicker and sock draw, it that wrong?

 

[paulm]

The video is interesting and highlights that PU is a a lot softer than PR and thats about it really. They do turn differently and you can get a good finish on both but PR is 1/2 the price of PU. I like Alumilite (PR) because thats all I've had a go at moulding but am going to have a go at PU later in the year when I think that temperature is more critical.

 

[rayf6604]

The video is interesting and highlights that PU is a a lot softer than PR and thats about it really. They do turn differently and you can get a good finish on both but PR is 1/2 the price of PU. I like Alumilite (PR) because thats all I've had a go at moulding but am going to have a go at PU later in the year when I think that temperature is more critical.

I'm confused, I thought that Alumilite is polyurethane PU and that PR is polyester and the later was the the cheaper?

 

[AndyC65]

I've been using it to freshen my knicker and sock draw, it that wrong?

Yes, you should be keeping them in separate draws - avoids confusion

 

[Buckeye]

I'm confused, I thought that Alumilite is polyurethane PU and that PR is polyester and the later was the the cheaper?

You are correct Alumilite is PU resin.

Peter

 

[Tephy]

The video is interesting and highlights that PU is a a lot softer than PR and thats about it really. They do turn differently and you can get a good finish on both but PR is 1/2 the price of PU. I like Alumilite (PR) because thats all I've had a go at moulding but am going to have a go at PU later in the year when I think that temperature is more critical.

Alumilite is an American manufacturer of polyurethane resin

 

[Jim]

This guy is biased and can be clearly seen in the video ..

 

[Johnwhitlock]

I have had one go with a clear casting resin from hobby craft, there was no styrene smell or any odour come to that but it was very brittle. If it's so brittle it's not the one for me, now I'm looking for something else but I have no pressure pot.

 

[Penpal]

Why I love timber.

Peter.

 

[Jim]

I have had one go with a clear casting resin from hobby craft, there was no styrene smell or any odour come to that but it was very brittle. If it's so brittle it's not the one for me, now I'm looking for something else but I have no pressure pot.

PR can be very brittle if you add to much catalyst, also being to heavy handed with the tools .. Taking small cuts and sharp tools PR is as good as any resin for casting ..